The association of hydrocephalus and intramedullary spinal-cord tumor with leptomeningeal spread is described in a 20 month-old boy. The pathogenesis of increased intracranial pressure in spinal cord tumor is discussed. Meningeal gliomatosis is rare and is more often observed in the follow-up of cerebral gliomas. It exceptionally occurs in patients without known cerebral or spinal tumor. Such a tumor often occurs in young patients and has a poor prognosis.